Browsing by Author "Lin, Pu-Hsuan"

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A K-BEST ORTHOGONAL MATCHING PURSUIT FOR COMPRESSIVE SENSING
(2013)
Lin, Pu-Hsuan
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Tsai, Shang-Ho
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Chuang, Gene C. -H.
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
This paper proposes an orthogonal matching pursuit (OMP-) based recovering algorithm for compressive sensing problems. This algorithm can significantly improve recovering performance while it can still maintain reasonable computational complexity. Complexity analysis and simulation results are provided for the proposed algorithm and compared with other popular recovering schemes. We observe that the proposed algorithm can significantly improve the exact recovering performance compared to the OMP scheme. Moreover, in the cases with high compressed ratio, the proposed algorithm can even outperform the benchmark performance achieved by the subspace programming and linear programming.
Compressed Sensing Recovery Algorithms and VLSI Implementation
(2013)
Lin, Kuan-Ting
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Yang, Kai-Jiun
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Lin, Pu-Hsuan
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Tsai, Shang-Ho
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電機工程學系
This paper proposes two recovery algorithms modified from subspace pursuit(SP) for compressed sensing problems. These algorithms can reduce the complexity of SP and maintain high recovery rate. Complexity analysis and simulation results are provided to demonstrate the improvements. Additionally this work has implemented the VLSI circuit APR of the proposed algorithm using TSMC 90 nm process. The target clock frequency is 100MHz, and the corresponding APR dimension is 11.69mm(2). Based on the post-layout simulation the average power consumption is 431 mW.
Performance Analysis and Algorithm Designs for Transmit Antenna Selection in Linearly Precoded Multiuser MIMO Systems
(2012-05-01)
Lin, Pu-Hsuan
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Tsai, Shang-Ho
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電機工程學系
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Department of Electrical and Computer Engineering
This paper investigates transmit antenna selection for linearly precoded multiuser multiple-input-multiple-output (MU-MIMO) systems. First, in some precoded single-user MIMO systems, using all transmit antennas does not always lead to the best performance due to ill-conditioned channel matrices. This condition motivates us to investigate whether a similar result can be obtained in MU-MIMO systems. Based on the derived analytical results, we found that, for a given number of transmit antennas, decreasing the number of active transmit antennas [ number of radio frequency (RF) units] always degrades system performance in the linearly precoded MU-MIMO systems. However, in practical systems, RF units are expensive. To reduce the hardware cost, antenna selection is usually used to reduce the number of RF units. Thus, we further analyze the performance loss due to transmit antenna selection (TAS). These analytical results provide good design references for using TAS in practical systems. Moreover, based on the analytical results, we proposed several simple TAS algorithms for linearly precoded MU-MIMO systems. Complexity analysis and simulation results show that the computational complexity of the proposed algorithms can significantly be reduced, whereas the performance is still comparable with the optimal selection scheme. As a result, the analyzed results enable us to better understand how TAS affects the MU-MIMO systems. In addition, the proposed algorithms make TAS more feasible to be used in practical systems.
REDUCED COMPLEXITY MULTIMODE ANTENNA SELECTION WITH BIT ALLOCATION FOR ZERO-FORCING RECEIVER
(2012)
Yeh, Wan-Chen
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Tsai, Shang-Ho
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Lin, Pu-Hsuan
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
In this paper, we investigate multimode antenna selection for zero forcing receiver to maximize the overall data rate. The optimal selection scenario can be achieved by exhaustive search. However, antenna selection using exhaustive search leads to complicated computational burden. To reduce the complexity, we propose a greedy search algorithm for antenna selection. Using the proposed algorithm, the computations can be greatly reduced while the achievable data rate is nearly the same with exhaustive search. Moreover, generally fixed bit budgets are used in practical design. Hence, we propose to use water-filling bit allocation to further improve the performance of the proposed antenna selection scheme. Simulation results are provided to show the advantages of the proposed multimode antenna selection with bit allocation.
Transmit Antenna Selection with Linear Precoding in MIMO Multiuser Systems
(2010)
Lin, Pu-Hsuan
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Tsai, Shang-Ho
;
Chuang, Chun-Hsiung
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電機工程學系
;
Department of Electrical and Computer Engineering
In this paper, we propose a low-complexity transmit antenna selection algorithm for MIMO multiuser channels. This algorithm greedily finds the optimal transmit antenna subset in base station. When the transmit power for individual data streams is equal, the proposed algorithm can be applied to the zero-forcing and the MMSE precoding schemes to further simplify the computational complexity. Simulation results show that the proposed low-complexity suboptimal antenna selections can achieve very close performance with the optimal antenna selection scheme in [6]. As a result, a good trade-off between complexity and performance is attained by the proposed antenna selection schemes.